This invention pertains generally to heating apparatus and more particularly to heating apparatus utilizing solar energy.
In the past, there have been attempts to collect the sun's rays and utilize the heat derived therefrom. In one type of apparatus heretofore provided for this purpose, a liquid to be heated is passed through a heat exchanger which is exposed directly to the sun's rays. Although simple and inexpensive to operate, this type of heating apparatus has a low collection efficiency, and it requires a relatively large heat exchanger to produce an appreciable amount of heat.
Another type of solar heating apparatus heretofore provided includes means for focusing the sun's rays to concentrate the energy contained therein on a suitable collector containing the medium to be heated. Such containers are substantially more efficient than the non-focusing type, but they have a serious disadvantage in that they collect energy from only a narrow angular field and they must be repositioned frequently to keep the sun within this field. These heaters are not suitable for applications, such as the heating and cooling of buildings, where permanent installation without daily or seasonal repositioning is desired.